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1.
Plast Reconstr Surg Glob Open ; 12(6): e5870, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38855135

RESUMO

Chronic lymphocytic leukemia is characterized by the accumulation of mature CD5-positive B-cells in the lymphoid organs.1 Extranodal involvement occurs in up to 10% of cases and can arise in various tissues, including the orbit. Less than 400 cases of orbital lymphoma are diagnosed per year in the United States, typically manifesting as a form of B-cell non-Hodgkin lymphoma, with extranodal marginal zone B-cell lymphoma being the most common subtype. Orbital lymphoma typically presents with proptosis and a palpable mass; however, patients may also have a relatively benign examination. Here, we present a 76-year-old man with symmetric dermatochalasis and marked fat prolapse of all four lids, who was incidentally diagnosed with secondary orbital lymphoma in all four eyelids during a cosmetic four lid blepharoplasty. His history was significant for RAI Stage 0 chronic lymphocytic leukemia diagnosed 15 years before consultation. Orbital lymphoma presenting as orbital fat prolapse has only been reported a few times in the literature. To our knowledge, this is the first case of secondary orbital lymphoma in all four eyelids found incidentally during an aesthetic four lid blepharoplasty.

2.
Nutr Diabetes ; 13(1): 20, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37938224

RESUMO

BACKGROUND/OBJECTIVES: Nutrition and obesity researchers often dichotomize or discretize continuous independent variables to conduct an analysis of variance to examine group differences. We describe consequences associated with dichotomizing and discretizing continuous variables using two cross-sectional studies related to nutrition. SUBJECTS/METHODS: Study 1 investigated the effects of health literacy and nutrition knowledge on nutrition label accuracy (n = 612). Study 2 investigated the effects of cognitive restraint and BMI on fruit and vegetable (F/V) intake (n = 586). We compare analytic approaches where continuous independent variables were either discretized/dichotomized or analyzed as continuous variables. RESULTS: In Study 1, dichotomization of health literacy and nutrition knowledge for 2 × 2 ANOVA revealed health literacy had an effect on nutrition label accuracy. Nutrition knowledge has an effect on nutrition label accuracy, but the health literacy by nutrition knowledge interaction was not significant. When analyzed using regression, the nutrition knowledge effect was significant. The simple effect of health literacy was also significant when health literacy equals zero. Finally, the quadratic effect of health literacy was negative and significant. In Study 2, dichotomization and discretization of cognitive restraint and BMI were used for three ANOVAs, which discretized BMI in three ways. For all ANOVAs, the BMI main effect for predicting fruit and vegetable intake was significant, the interaction between BMI and cognitive restraint was non-significant, and cognitive restraint was only significant when both variables were dichotomized. When analyzed using regression, the continuous mean-centered variables, and their interaction each significantly predicted F/V intake. CONCLUSIONS: Dichotomizing continuous independent variables resulted in distortions of effect sizes across studies, an inability to assess the quadratic effect of health literacy, and an inability to detect the moderating effect of BMI. We discourage researchers from dichotomizing and discretizing continuous independent variables and instead use multiple regression to examine relationships between continuous independent and dependent variables.


Assuntos
Ingestão de Alimentos , Estado Nutricional , Humanos , Estudos Transversais , Obesidade
3.
Orthop J Sports Med ; 10(9): 23259671221117606, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36081408

RESUMO

Background: Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) is an advanced imaging technique that is purported to quantify cartilage damage in acute and chronic joint disease and predict periacetabular osteotomy (PAO) outcomes. There is a paucity of literature relating dGEMRIC values to arthroscopic findings before PAO and postoperative outcomes after PAO. Purpose: To assess the utility and validity of dGEMRIC as a preoperative and prognostic assessment tool of cartilage status and integrity as it relates to intraoperative findings and midterm postoperative outcomes after PAO. Study Design: Case series; Level of evidence, 4. Methods: We analyzed a cohort of 58 patients (70 hips) with a median age of 30.1 years (range, 15-50) with hip dysplasia who underwent hip arthroscopy, followed by a PAO with preoperative dGEMRIC. The primary outcome measures were intraoperative assessment and correlation with cartilage damage (presence of cartilage flap, Outerbridge grade of the acetabulum and femoral head). Secondary outcome measures were postoperative patient-reported outcome (PRO) scores, including the International Hip Outcome Tool and Non-arthritic Hip Score. Correlation analyses were performed to determine the relationship between dGEMRIC values and (1) PROs and (2) intraoperative assessment of cartilage damage. Results: There were significant negative linear relationships between dGEMRIC values and the primary outcome measures: presence of a cartilage flap (coronal, P = .004; sagittal, P < .001), Outerbridge grade of acetabular articular cartilage lesion (coronal, P = .002; sagittal, P = .003), and Outerbridge grade of femoral head articular cartilage lesion (coronal, P = .001; sagittal, P < .001). Despite significant overall improvement in all patients, there was no significant correlation between preoperative dGEMRIC values and improvement in PROs from presurgery to latest postoperative follow-up (median, 2.2 years; range, 1.0-5.0 years). Conclusion: Although dGEMRIC values (sagittal and coronal) were significant predictors of the intraoperative presence of cartilage flaps and overall cartilage integrity, they were not associated with midterm outcomes after PAO.

5.
Phys Rev Lett ; 128(2): 023001, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35089737

RESUMO

We present a measurement of the hydrogen 2S_{1/2}-8D_{5/2} transition performed with a cryogenic atomic beam. The measured resonance frequency is ν=770649561570.9(2.0) kHz, which corresponds to a relative uncertainty of 2.6×10^{-12}. Combining our result with the most recent measurement of the 1S-2S transition, we find a proton radius of r_{p}=0.8584(51) fm and a Rydberg constant of R_{∞}=10973731.568332(52) m^{-1}. This result has a combined 3.1σ disagreement with the Committee on Data for Science and Technology (CODATA) 2018 recommended value.

6.
Front Artif Intell ; 4: 649917, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34505055

RESUMO

In liquid argon time projection chambers exposed to neutrino beams and running on or near surface levels, cosmic muons, and other cosmic particles are incident on the detectors while a single neutrino-induced event is being recorded. In practice, this means that data from surface liquid argon time projection chambers will be dominated by cosmic particles, both as a source of event triggers and as the majority of the particle count in true neutrino-triggered events. In this work, we demonstrate a novel application of deep learning techniques to remove these background particles by applying deep learning on full detector images from the SBND detector, the near detector in the Fermilab Short-Baseline Neutrino Program. We use this technique to identify, on a pixel-by-pixel level, whether recorded activity originated from cosmic particles or neutrino interactions.

7.
PLoS One ; 16(6): e0253578, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34166421

RESUMO

RATIONALE: There is little doubt that aerosols play a major role in the transmission of SARS-CoV-2. The significance of the presence and infectivity of this virus on environmental surfaces, especially in a hospital setting, remains less clear. OBJECTIVES: We aimed to analyze surface swabs for SARS-CoV-2 RNA and infectivity, and to determine their suitability for sequence analysis. METHODS: Samples were collected during two waves of COVID-19 at the University of California, Davis Medical Center, in COVID-19 patient serving and staff congregation areas. qRT-PCR positive samples were investigated in Vero cell cultures for cytopathic effects and phylogenetically assessed by whole genome sequencing. MEASUREMENTS AND MAIN RESULTS: Improved cleaning and patient management practices between April and August 2020 were associated with a substantial reduction of SARS-CoV-2 qRT-PCR positivity (from 11% to 2%) in hospital surface samples. Even though we recovered near-complete genome sequences in some, none of the positive samples (11 of 224 total) caused cytopathic effects in cultured cells suggesting this nucleic acid was either not associated with intact virions, or they were present in insufficient numbers for infectivity. Phylogenetic analysis suggested that the SARS-CoV-2 genomes of the positive samples were derived from hospitalized patients. Genomic sequences isolated from qRT-PCR negative samples indicate a superior sensitivity of viral detection by sequencing. CONCLUSIONS: This study confirms the low likelihood that SARS-CoV-2 contamination on hospital surfaces contains infectious virus, disputing the importance of fomites in COVID-19 transmission. Ours is the first report on recovering near-complete SARS-CoV-2 genome sequences directly from environmental surface swabs.


Assuntos
COVID-19/genética , Genoma Viral , Hospitais de Ensino , Filogenia , SARS-CoV-2/genética , Análise de Sequência de RNA , Animais , COVID-19/epidemiologia , COVID-19/transmissão , Chlorocebus aethiops , Humanos , SARS-CoV-2/isolamento & purificação , Células Vero
8.
Nano Lett ; 21(13): 5547-5554, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34185540

RESUMO

The particle-like magnetic skyrmion or skyrmion lattice (SkX) formation has promoted strong application and fundamental science interests. Despite extensive research, the kinetic of the SkX development is much less understood because of the ultrafast spin rotation and high sensitivity to external perturbations. Here, using in situ Lorentz transmission electron microscopy, we successfully measured the dynamics of SkX formation from the conical phase with precise control of both the temperature and the magnetic field. We discovered that the Avrami equation can accurately describe the transition process with an initial Avrami constant around 1, suggesting that the rate-limiting step for the quasiparticle lattice formation is one-dimensional heterogeneous nucleation of individual skyrmions. A modified Arrhenius rate law is established, with an energy barrier that has a square-root dependence on temperature and a quadratic dependence on the magnetic field. This study paves the way toward precise and predictable manipulation of topological spin structures.

9.
Dev Psychol ; 57(4): 489-505, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36101892

RESUMO

The Midwest Child-Parent Center (CPC) Expansion began preschool implementation in fall 2012 in five Minnesota and Illinois districts. This study reports preschool and kindergarten impact findings for the Saint Paul Public School District. It is the first impact study of CPC outside of Chicago. After documenting that implementation quality was relatively high on the six CPC elements (effective learning, collaborative leadership, aligned curriculum, parent involvement, professional development, and continuity and stability), matched-group analyses of 433 students utilizing propensity score weighting indicated that CPC participants had significantly higher levels of language and literacy proficiency in both preschool and kindergarten than comparison-group participants in the usual district preschool and kindergarten programs. Overall composite effect sizes were .51 SD at the end of preschool and .36 SD at the end of kindergarten, which translate to performance gains of nearly half of a year. At the end of kindergarten, 61.0% of CPC participants met the district's literacy benchmark compared to 47.4% for the comparison group. We also found that parents of CPC participants attended a significantly greater number of school events and workshops. However, no differences favoring CPC were detected for preschool or kindergarten attendance. Impacts were generally similar for Dual Language Learners. Students with two years of CPC (preschool and kindergarten) showed better performance in kindergarten reading stage and fluency than comparison group but not compared to the 1-year group. This was similar for Dual Language Learners. Findings indicate that the CPC program shows evidence that it can be effectively scaled and that the program yields impacts in preschool and kindergarten that exceed the usual early childhood programming in Saint Paul.


Assuntos
Alfabetização , Instituições Acadêmicas , Pré-Escolar , Escolaridade , Humanos , Pais , Leitura
10.
Eval Rev ; 44(5-6): 379-409, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33307776

RESUMO

In a previous study of the Child-Parent Centers (CPC) education program, preschool participation was linked to a 4.6 percentage point reduction (26%) in depressive symptoms at ages 22-24 over the matched comparison group enrolling the usual programs. The present study reanalyzed these data in the Chicago Longitudinal Study to address potential attrition bias since more than a quarter of the sample was missing on the outcome. Using inverse probability weighting (IPW) involving 32 predictors of sample retention, findings for the 1,142 participants growing up in high-poverty neighborhoods indicated that CPC participation was associated with a 7.1 percentage point reduction (95% CI = [-9.7, -5.4]) in one or more depressive symptoms (39% reduction over the comparison group). Although this marginal effect was within the confidence interval of the original study (95% CI = [-9.5, 0.3]), the 54% increase in the point estimate is substantial and of practical significance, suggesting underestimation in the prior study. Alternative analysis of different predictors and IPW models, including adjustments for program selection and attrition together, yielded similar results. Findings indicate that high-quality early childhood programs continue to be an important strategy for the prevention of depression and its debilitating effects on individuals and families.


Assuntos
Depressão/prevenção & controle , Promoção da Saúde/métodos , Pobreza/estatística & dados numéricos , Qualidade de Vida/psicologia , Adolescente , Adulto , Criança , Proteção da Criança/estatística & dados numéricos , Pré-Escolar , Depressão/epidemiologia , Humanos , Estudos Longitudinais , Masculino , Pontuação de Propensão , Fatores de Risco , Adulto Jovem
11.
Nutr Clin Pract ; 35(6): 1094-1100, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33078441

RESUMO

BACKGROUND: Standardized diagnostic indicators for malnutrition using growth percentile z-scores (weight for length or body mass index [BMI]) and mid-upper arm circumference (MUAC) z-scores are being used in clinical practice; however, their application to the pediatric cystic fibrosis (CF) population is not well described. In this study, we aim to compare growth percentile z-scores and MUAC z-scores in diagnosing and classifying malnutrition in children with CF and assess the relationship between their degree of malnourishment and corresponding pulmonary function tests (PFTs). METHODS: In this retrospective observational outpatient study of 49 pediatric CF patients, data were collected on baseline characteristics, anthropometrics, and PFTs over 12 months. Agreement in malnutrition diagnoses was quantified by Cohen κ statistics. Pearson test assessed the correlation between MUAC and BMI z-scores as well as PFTs and anthropometrics. Serial anthropometrics and PFTs were obtained and compared for a subset of patients (n = 28). RESULTS: Growth percentile and MUAC z-scores were positively correlated in diagnosing malnutrition (Pearson correlation r = 0.87), but MUAC z-scores identified more patients as malnourished compared with growth percentile z-scores (49% vs 12%, Cohen κ of 0.22 [95% CI, 0.04-0.40]). There was no significant relationship between anthropometrics and PFTs. MUAC z-scores increased significantly over time, but BMI z-scores did not show this trend. CONCLUSIONS: Our small-scale data suggest a promising role for MUAC z-scores in classifying malnutrition and in measuring changes in nutrition status over time in pediatric CF.


Assuntos
Transtornos da Nutrição Infantil , Fibrose Cística , Desnutrição , Adolescente , Antropometria , Braço/anatomia & histologia , Peso Corporal , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Desnutrição/diagnóstico , Estudos Retrospectivos
13.
Eur J Surg Oncol ; 46(10 Pt A): 1902-1907, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32340819

RESUMO

OBJECTIVES: In the Netherlands, limited variability exists in performance of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) among centers treating colorectal peritoneal metastases (PM), except for the intraperitoneal drug administration. This offers a unique opportunity to investigate any disparities in survival between the two most frequently used HIPEC regimens worldwide: mitomycin C (MMC) and oxaliplatin. METHODS: This was a comparative, population-based cohort study of all Dutch patients diagnosed with synchronous colorectal PM who underwent CRS-HIPEC between 2014 and 2017. They were retrieved from the Netherlands Cancer Registry. Main outcome was overall survival (OS). The effect of the intraperitoneal drug on OS was investigated using multivariable Cox regression analysis. RESULTS: In total, 297 patients treated between 2014 and 2017 were included. Among them, 177 (59.6%) received MMC and 120 (40.4%) received oxaliplatin. Only primary tumor location was different between the two groups: more left-sided colon in the Oxaliplatin group (47.5% vs. 33.3%, respectively, p=0.048). The 1-, 2- and 3-year OS were 84.6% vs. 85.8%, 61.6% vs. 63.9% and 44.7% vs. 53.5% in patients treated with MMC and oxaliplatin, respectively. Median OS was 30.7 months in the MMC group vs. 46.6 months in the oxaliplatin group (p=0.181). In multivariable analysis, no influence of intraperitoneal drug on survival was observed (adjusted HR 0.77 [0.53-1.13]). CONCLUSIONS: Long-term survival between patients treated with either MMC or oxaliplatin during CRS-HIPEC was not significantly different.


Assuntos
Adenocarcinoma/terapia , Antineoplásicos/uso terapêutico , Neoplasias Colorretais/terapia , Procedimentos Cirúrgicos de Citorredução , Quimioterapia Intraperitoneal Hipertérmica/métodos , Mitomicina/uso terapêutico , Oxaliplatina/uso terapêutico , Neoplasias Peritoneais/terapia , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Adenocarcinoma Mucinoso/patologia , Adenocarcinoma Mucinoso/secundário , Adenocarcinoma Mucinoso/terapia , Idoso , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Neoplasias Peritoneais/secundário , Modelos de Riscos Proporcionais , Taxa de Sobrevida , Resultado do Tratamento
14.
Cerebellum ; 19(3): 437-445, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32170655

RESUMO

Dysphagia is a common symptom in neurodegenerative disorders and is generally associated with increased mortality. In the clinical care setting of ataxia patients, no systematical and standardized assessment of dysphagia is employed. Its impact on patients' health-related quality of life is not well understood. To assess the impact of dysphagia in ataxia patients on diet, body weight, and health-related quality of life. We conducted a large survey using self-reported questionnaires for swallowing-related quality of life (Swal-QOL) and a food frequency list in combination with retrospective clinical data of 119 patients with cerebellar ataxia treated in the neurological outpatient clinic of a large German university hospital. Seventeen percent of ataxia patients suffered from dysphagia based on the Swal-QOL score. Less than 1% of all patients reported dysphagia as one of their most disabling symptoms. Dysphagia was associated with unintentional weight loss (p = 0.02) and reduced health-related quality of life (p = 0.01) but did not affect individual nutritional habits (p > 0.05; Chi-squared test). Dysphagia is a relevant symptom in cerebellar ataxia. A systematic screening for dysphagia in patients with cerebellar ataxia would be desirable to enable early diagnosis and treatment.


Assuntos
Ataxia Cerebelar/fisiopatologia , Ataxia Cerebelar/psicologia , Transtornos de Deglutição/fisiopatologia , Transtornos de Deglutição/psicologia , Qualidade de Vida/psicologia , Inquéritos e Questionários , Adulto , Idoso , Idoso de 80 Anos ou mais , Ataxia Cerebelar/diagnóstico , Estudos Transversais , Deglutição/fisiologia , Transtornos de Deglutição/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Nano Lett ; 20(7): 4731-4738, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32202799

RESUMO

Real-space topological magnetic structures such as skyrmions and merons are promising candidates for information storage and transport. However, the microscopic mechanisms that control their formation and evolution are still unclear. Here, using in situ Lorentz transmission electron microscopy, we demonstrate that skyrmion crystals (SkXs) can nucleate, grow, and evolve from the conical phase in the same ways that real nanocrystals form from vapors or solutions. More intriguingly, individual skyrmions can also "reproduce" by division in a mitosis-like process that allows them to annihilate SkX lattice imperfections, which is not available to crystals made of mass-conserving particles. Combined string method and micromagnetic calculations show that competition between repulsive and attractive interactions between skyrmions governs particle-like SkX growth, but nonconservative SkX growth appears to be defect mediated. Our results provide insights toward manipulating magnetic topological states by applying established crystal growth theory, adapted to account for the new process of skyrmion mitosis.

16.
Rev Sci Instrum ; 91(1): 013201, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012573

RESUMO

Precision spectroscopy of hydrogen often relies on effusive thermal atomic beams, and the uncertainty in the velocity distribution of these beams can introduce systematic errors and complicate lineshape models. Here, we present an apparatus capable of high signal-to-noise studies of these velocity distributions at cryogenic temperatures for both ground state (1S) and metastable (2S) hydrogen using a simple time-of-flight technique. We also investigate how the cryogenic nozzle geometry affects these results.

17.
Eur J Prosthodont Restor Dent ; 28(1): 36-42, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32040892

RESUMO

INTRODUCTION: In a prospective study, the clinical performance of chairside-fabricated partial-crowns made of zirconia-reinforced lithiumsilicate (ZLS)-ceramic was evaluated after 2 years. MATERIALS AND METHODS: 45 patients (28 female/17 male) underwent restoration with 61 chairside-fabricated ZLS partial-crowns on vital premolars and molars. In variation from the manufacturer's recommendations (minimum material thickness (MMT)=1.0 mm), partial-crowns with reduced material thicknesses were fabricated: group 1, MMT=0.5-0.74 mm (n=31); group 2, MMT=0.75-1.0 mm (n=30). The restorations were luted with either a self-adhesive cement (SAC) or the total-etch technique using a dual-curing composite cement (DC). The MMT and cementation technique (SAC vs. DC) were evaluated as possible covariates of the time-dependent survival (SVR) and success rate (SCR) using univariate log-rank-tests. RESULTS: Forty-four patients with 59 restorations participated in the 2-year follow-up examinations. In group 1 (n=31), there were 2 losses due to ceramic fracture (SVR: 94.0% (95% confidence interval (CI): 0.85-1)). In group 2, no losses were documented (SVR: 100%). In 2 restorations cemented with SAC, recementation was necessary (overall SCR: 93% (CI: 0.87-1)). CONCLUSION: To avoid early material-related fractures, observing the recommended minimum thickness of 1.0 mm is essential. However, further validation of these results in studies with longer observational periods is required.


Assuntos
Coroas , Lítio , Cerâmica , Desenho Assistido por Computador , Porcelana Dentária , Planejamento de Prótese Dentária , Falha de Restauração Dentária , Feminino , Humanos , Masculino , Teste de Materiais , Estudos Prospectivos , Silicatos , Zircônio
18.
AJNR Am J Neuroradiol ; 41(2): 343-350, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31974079

RESUMO

BACKGROUND AND PURPOSE: Spinal cord atrophy is commonly measured from cerebral MRIs, including the upper cervical cord. However, rescan intraparticipant measures have not been investigated in healthy cohorts. This study investigated technical and rescan variability in the mean upper cervical cord area calculated from T1-weighted cerebral MRIs. MATERIALS AND METHODS: In this retrospective study, 8 healthy participants were scanned and rescanned with non-distortion- and distortion-corrected MPRAGE sequences (11-50 sessions in 6-8 months), and 50 participants were scanned once with distortion-corrected MPRAGE sequences in the Day2day daily variability study. From another real-world observational cohort, we collected non-distortion-corrected MPRAGE scans from 27 healthy participants (annually for 2-4 years) and cross-sectionally from 77 participants. Statistical analyses included coefficient of variation, smallest real difference, intraclass correlation coefficient, Bland-Altman limits of agreement, and paired t tests. RESULTS: Distortion- versus non-distortion-corrected MPRAGE-derived mean upper cervical cord areas were similar; however, a paired t test showed incomparability (t = 11.0, P = <.001). Higher variability was found in the mean upper cervical cord areas calculated from an automatic segmentation method. Interrater analysis yielded incomparable measures in the same participant scans (t = 4.5, P = <.001). Non-distortion-corrected mean upper cervical cord area measures were shown to be robust in real-world data (t = -1.04, P = .31). The main sources of variability were found to be artifacts from movement, head/neck positioning, and/or metal implants. CONCLUSIONS: Technical variability in cord measures decreased using non-distortion-corrected MRIs, a semiautomatic segmentation approach, and 1 rater. Rescan variability was within ±4.4% for group mean upper cervical cord area when MR imaging quality criteria were met.


Assuntos
Medula Cervical/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/normas , Adulto , Algoritmos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/normas , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Controle de Qualidade , Reprodutibilidade dos Testes , Estudos Retrospectivos
19.
Mar Environ Res ; 151: 104776, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31474311

RESUMO

Active hydrothermal vents are small-scale habitats hosting endemic fauna in a well-defined zonation around fluid effluents. The fauna of inactive hydrothermal vents and its relation to active vents and non-vent area is poorly known. Characterizing inactive areas is prerequisite to establish protected areas, especially in the context of potential seafloor massive sulfide mining, which targets inactive sites. Hierarchical clustering and Distance-based Redundancy Analysis revealed five assemblages, with significantly associated substrate types: I) active hydrothermal vent, II) periphery, III) inactive hydrothermal vent and IV) soft- and V) hard-substrate within the non-vent area. For the first time, a unique inactive faunal assemblage could be identified within the hydrothermally extinct inactive Gauss field and on adjacent hard substrates. The spatial separation from the active Edmond field and periphery and the non-vent area indicates the existence of an inactive assemblage.


Assuntos
Biodiversidade , Ecossistema , Fontes Hidrotermais , Animais , Mineração , Sulfetos
20.
Appl Opt ; 58(7): 1657-1661, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30874196

RESUMO

We demonstrate a 1.4 W continuous-wave (CW) laser at 243.1 nm. The radiation is generated through frequency quadrupling the output of a ytterbium-doped fiber amplifier system. which produces >10 W of CW power at 972.5 nm. We demonstrate absolute frequency control by locking the laser to an optical frequency comb and exciting the 1S-2S transition in atomic hydrogen. This frequency-stabilized, high-power deep-UV laser is of significant interest for precision spectroscopy of simple and exotic atoms, two-photon laser cooling of hydrogen, and Raman spectroscopy.

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